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The Apple Watch may be able to accurately detect hypertension and sleep apnea, according to a new study published today by the University of California San Francisco (UCSF) and Cardiogram, a company that's developed an app that breaks down heart rate data collected by the Apple Watch.

Using data collected from 6,115 Apple Watch owners and interpreted by Cardiogram's deep neural network "DeepHeart," the study found that the neural network was able to recognize hypertension (aka high blood pressure) with 82 percent accuracy and sleep apnea with 90 percent accuracy.

applewatchheartrate2.jpg

Based on previously-established principles suggesting people with low heart rate variability are 1.44x more likely to develop hypertension and that algorithms can accurately determine sleep apnea by beat-to-beat rate variability, Cardiogram and UCSF researchers recruited people for a Health eHeart study and then trained the DeepHeart neural network to detect new variables.

Cardiogram co-founder Brandon Ballinger told TechCrunch the DeepHeart neural network was trained using data from 70 percent of participants, and then tested on the remaining 30 percent who were not used for training purposes. Of the 6,115 people who participated in the study, sleep apnea was detected in 1,016 participants and hypertension in 2,230.

The study results are promising enough that Cardiogram believes with additional research, wearables like the Apple Watch could be used as a cost effective way to test for hypertension and sleep apnea.
The result was accuracy high enough to support feasible, cost-effective, widely-deployable screening of hypertension and sleep apnea.

For sleep apnea, DeepHeart achieved an accuracy (c-statistic, or AUC ROC) of 90%, with several attractive operating points. For example, we can detect 52% of sleep apnea ( compared to 20% today) with a specificity of 97%. If a specificity of 82% is acceptable, then we can detect even more sleep apnea, about 75% of people. For hypertension, the AUC was 0.82, with an example operating point of 81% sensitivity at 63.2% specificity.
Cardiogram says that peer-reviewed clinical research will be necessary to further determine whether wearables are able to screen for major health conditions like sleep apnea and hypertension, but the research results will be translated into future Cardiogram features.

Cardiogram previously used the same neural network and Apple Watch data to determine that the Apple Watch is able to detect abnormal heart rate rhythms with 97 percent accuracy. This has led Apple team up with Stanford for its own study on whether the Apple Watch can detect abnormal health rhythms and common heart problems.

In the future, Cardiogram plans to expand its research to additional conditions like pre-diabetes and diabetes.

Article Link: Study Suggests Apple Watch Heart Rate Monitor Can Detect Hypertension and Sleep Apnea
 
Apple is entering the health industry, revolutionizing self care... but not battery tech.
 
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Too bad the battery doesn’t last long enough to wear all night and be charged for the next day...
I used to think that too, but I've recently started wearing my watch to bed to monitor my sleep with the app Sleep Watch.

Turns out getting the battery to last for me throughout the day and night was just a matter of changing my charging habits. Now I charge the watch after I get up while I'm getting ready. Usually charges enough to make it through the day and the next night... and that's with a Series 0.
 
Wow, that is really amazing all the things the Apple Watch can detect even without adding any more sensors. I figured all this stuff would be coming in the future with additional sensors. The product that keeps getting better


Too bad the battery doesn’t last long enough to wear all night and be charged for the next day...

True... however it’s really easy to charge 30 mins at morning and night while getting ready for bed/morning. That’s what I’ve been doing for nearly 2 years. 60 minutes of charging (split between morning and night) has been enough for me most of the time, because the watch charges so quickly. Doing this actually increases the longevity of the watch by keeping it between 40-80% (typically about where mine stays), rather than allowing it to drain low and then sit on the charger all night long. Obviously depending on your schedule you might have to adjust, but I haven’t had any issues.
 
Too bad the battery doesn’t last long enough to wear all night and be charged for the next day...
Speak for yourself. The Series 3 42mm lasts about 2.5 days for me and fully charges in 45 min. It gets a full days charge from about 15-20 min.

I charged it last night while taking a shower. Wore it to bed for use as my alarm and wore it all day without charging it again at work using it (email, messages, Things, the time) and it’s at 67%. If I were to throw it on the charger it would be fullly charged in 10-15 min. That’s about the length of my shower and getting dressed.

If I sleep with it on I lose about 4% overnight (turning theatre mode on helps).

The battery life issue has definitely been solved.
 
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I used to think that too, but I've recently started wearing my watch to bed to monitor my sleep with the app Sleep Watch.

Turns out getting the battery to last for me throughout the day and night was just a matter of changing my charging habits. Now I charge the watch after I get up while I'm getting ready. Usually charges enough to make it through the day and the next night... and that's with a Series 0.

If you enable Theater Mode you get even more time since the display won't come on every time you move around in bed. If you also put it in AirPlane Mode since it's unlikely that you'll need to get notifications whilst sleeping you can further reduce the power usage.

I think it only registers like 1–3% over 6 hours with those two enabled. I also only charge while showering and getting ready, which is more than enough time to keep it charged for more than a day (although I do tend to shower twice a day).

I've even been able to get several days out of my Series 0 on a very long camping trip over a mountain where there was no cell signal by doing those steps, but that had no altimeter or GPS, so I'm not sure how that would work with my Series 3.
 
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I suppose it can based upon pulse rate. I have sleep apnea, about 15 events an hour, and testing showed that I could spike to about a 120 pulse when an event happened. I use a bpap machine at night. Down to about 4-7 events now.
 
Too bad the battery doesn’t last long enough to wear all night and be charged for the next day...

Through management. I use my Apple Watch1 day and night. How is this possible. One the Apple Watch charges rather quickly. I charge it in the evening when the battery is low. Understand the battery drain caused by activity and things like notifications. After Apple Watch charges in the evening, set do not disturb bedtime to wakeup. My experience sleeping with the Apple Watch, very little battery drain while sleeping. Infact generally less then 10% useage for 8 hours of sleep. Up in morning and off. If the day has an above average notifications, activity, and expecially using workouts, another 1 hours charge will be necessary. Can also select Theater mode at night, further reduces the battery drain. Any battery life increase will always be welcome. End of the day, my Apple Watch 1 will record a minimum of 20 hours with minimum effort on my part. More then enough to get plenty of data on my activity and sleep. Highly recommend the Apple Watch.
 
Too bad the battery doesn’t last long enough to wear all night and be charged for the next day...


My Apple Watch series 2 only needs to be charged for about 30 minutes a day, when I'm in the shower, and then I wear it day and night. This includes workouts at the gym. The key is to turn off a bunch of notifications, and be picky about what apps you put on the watch.
 
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If you enable Theater Mode you get even more time since the display won't come on every time you move around in bed. If you also put it in AirPlane Mode since it's unlikely that you'll need to get notifications whilst sleeping you can further reduce the power usage.

I think it only registers like 1–3% over 6 hours with those two enabled. I also only charge while showering and getting ready, which is more than enough time to keep it charged for more than a day (although I do tend to shower twice a day).

I've even been able to get several days out of my Series 0 on a very long camping trip over a mountain where there was no cell signal by doing those steps, but that had no altimeter or GPS, so I'm not sure how that would work with my Series 3.
Wowzers. That’s way better than I’m getting. I always use Theater Mode when I sleep and, while I don’t monitor it that closely, it seems like my battery usually drains like 10-15% while sleeping. I’ll monitor it more closely tonight. This is on a Series1. And when I took it backpacking (up in maroon bells) I kept it on airplane mode and was only able to get maybe 48 hours. But I brought a charger with me.
 
I've been using my S0 for sleep monitoring since I got my S3. Yesterday my S3 battery was still at 80% when I went to bed at 10:30, so I'm wondering if I really need to use the S0 for this anymore.
 
It appears that Apple Watch generally has enough battery to last at least one full day on a single charge in a typical scenario, regardless of generation. All-day watch wearers likely have made it a daily routine to charge the battery for about 30 to 60 minutes at a certain point of the day where wearing it is the least necessary. In my case it's that period about 1 to 2 hours before going to sleep where I chill out in front of a computer or TV and don't really move around much at all.

I don't do any of those battery-saving tricks (thanks for the heads up, though!) but typically the battery drain during sleep is in the order of 8-12% for my year-old Series 2. It still holds about 40-50% charge left at the end of the day, at my next charging cycle.
 
Too bad the battery doesn’t last long enough to wear all night and be charged for the next day...

Horsepucky. My S0 is 2 1/2 years old, and EVERY night it is on my wrist. I’m deaf, so it’s my alarm clock. In the morning I get up, put it on the charger (typically 40-60% charged) have my morning tea, and by the time I’ve had my shower it’s ready for the next 24 hours.

But, haters gonna hate.
 
Thanks everyone for the review of battery expectations. I've been considering getting a series 3 (don't own an Apple Watch atm), but had reservations about the battery life. Not many articles detailing charging/daily real world use, so this thread is very helpful in that regard. I'm not a huge consumer of data and doubt I would use the watch for making phone calls, so I think I would probably fall into a lesser battery drain category. I really like the sleep monitoring features and that was my primary concern of WHEN to charge, but it seems like 1-2 hours a day is enough time to charge, which I can easily part with it for that time.
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Too bad the battery doesn’t last long enough to wear all night and be charged for the next day...
I"m just curious. Based on the replies you've gotten contradicting your statement, how often do you have to charge your Apple Watch? Do you consider yourself a "heavy data consumer"?
 
It’s very easy to detect sleep apnoea using a simple oxygen monitor on your finger overnight.
 
Thanks everyone for the review of battery expectations. I've been considering getting a series 3 (don't own an Apple Watch atm), but had reservations about the battery life. Not many articles detailing charging/daily real world use, so this thread is very helpful in that regard. I'm not a huge consumer of data and doubt I would use the watch for making phone calls, so I think I would probably fall into a lesser battery drain category. I really like the sleep monitoring features and that was my primary concern of WHEN to charge, but it seems like 1-2 hours a day is enough time to charge, which I can easily part with it for that time.

If you're using it to make/receive phone calls you'll likely see yourself use more battery life and if you use it to make/receive phone calls without it going through Bluetooth or WiFi via your iPhone then it'll be even more pronounced.

While the iPhone X can do 21 hours of phone calls, which is well above the normal things we typically do with an iPhone these days, it's very much reversed with Watch. I haven't tested these times—and likely never will as I am not one to stay on the phone for long—but they say up to 1 hour on LTE and 3 hours via BT/WiFi (connected to the iPhones; but they also say it has an 18 hour battery life under typical conditions, which I'd argue is atypically low.

Screen Shot 2017-11-13 at 6.07.11 PM.jpg
 
Too bad the battery doesn’t last long enough to wear all night and be charged for the next day...

Oh man, this is so false. YES if you turn on every possible notification, but if you only use it for important ones, I'm getting 3-4 days out of this thing per charge, and I wear it all day and night. I last charged it Fri night, and I'm at 22%.

Series 3 LTE, but with the LTE turned off.
 
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